A D.C. Council member has taken a new approach to reeling in a pair of elusive witnesses to testify at hearings on Mayor Vincent C. Gray’s hiring practices: the mail.

Under council rules, a member can issue a subpoena by mail if reasonable attempts at in-person service prove unsuccessful. The summons must go out eight business days before the hearing.

Council member Mary M. Cheh’s office took advantage of this method Wednesday in light of failed attempts to serve Sulaimon Brown, who has said Gray confidante Lorraine A. Green and campaign consultant Howard Brooks gave him cash payments and promised him a job to stay in last year’s mayoral race and bash incumbent Adrian M. Fenty on Mr. Gray’s behalf.

Ms. Whiting resigned from her Parks and Recreation job after reports in The Washington Times about her undisclosed felony criminal record.

Ms. Green has agreed to appear at the hearing, but Mr. Brown and Ms. Whiting had not accepted subpoenas for the hearing as of Thursday. Therefore, Ms. Cheh turned to the U.S. Post Office.

“As far as I’m concerned, they are served,” she said Thursday.

Ms. Cheh initiated the personnel hearings in March to explore Mr. Brown’s accusations and other claims of cronyism and unlawfully high salaries paid to recently hired government employees.

Two marathon hearings produced an apology from Mr. Gray’s former chief of staff, Gerri Mason Hall, and accounts of how offspring of numerous city officials were hired.

Judy Banks, a former personnel director for Mr. Gray, testified for a second time last Friday. She stood by her version of events in hiring the son of a city Cabinet member’s son, even though three witnesses and a chain of e-mails contradict her testimony.

Mr. Brown has made it clear that he does not intend to participate in the hearings, although he did show up at two of them to hold court with reporters in the lobby of the John A. Wilson Building.

Ms. Cheh’s office has greater hopes for Ms. Whiting, who indicated she would be back in touch with the committee this week after helping her child move out of college in North Carolina.

The committee wants to explore the circumstances and documentation behind Ms. Whiting’s hiring and not cast aspersions about her personal history, according to Ms. Cheh.

“We don’t turn away people just because they have a criminal record,” she said.

Mr. Brooks and his son, Peyton Brooks, who obtained and then resigned from a city job, have asserted their Fifth Amendment right to remain silent.

Ms. Cheh said she may challenge Peyton Brooks’ assertion of the right, because no one has accused him of criminal behavior. To challenge the Fifth Amendment assertion in court, the committee must vote on a resolution and forward it to the full council.

Failing to pursue the issue may set a bad precedent, according to Ms. Cheh.

“This could be the easy way out for all witnesses,” she said.

Ms. Cheh said the stakes are higher for the elder Mr. Brooks, who may have a legitimate claim against self-incrimination in light of Mr. Brown’s accusations.